Piston



G. F. BRENT PISTON Filed Aug. 6, 1926 I 66 31mm; Geo ge 21576771 Patented July 31, 1928i UNITED STATES ii-7 0 PATENT OFFICE.

GEORGE F. BRENT, OF EUGENE, OREGON.

PISTON.

application filed August 6,- 1926. Serial No. 127,604.

cylinder, thereby to eliminate scoring of the cylinder and piston walls which might other-- wise result from this cause; to provide means for adjusting said flexible skirt portion to compensate for wear, and, above all, to provide a flexible skirt piston "which is strong, durable and thoroughly reliable and eflicient in use.

With the foregoing and other purposes in turesof construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawings and defined in the appended claims.

In the drawings, wherein like characters of reference denote corresponding parts in the different views Fig. 1 is a side elevation of a piston con-- structed in accordance with my invention;

Fig. 2, a' central longitudinal section therethrough;

' Fig. 3, a horizontal section on the line 33 of Fig. 2; i

Fig. 4, an enlarged detail perspective of one of the adjusting devices; and 3 Fig. 5, an enlarged detail elevation of one ofthe adjusting devices.

My improved piston, designated generally at 10, is of the usual well known form including a head 12 and a skirt portion 14,.

which latter is grooved externally, adjacent to the head, as at 1'6','for the reception of invention and for, a clear understanding thereof the wrist pin receiving bosses 18 may be considered as dividing the skirt portion 14of my piston into two semi-cylindrical halves which, in accordance with my invention, are slottedfin duplicate and peculiar fashion to produce, without materially afiecting the strength and rigidity of the skirt as an entirety,'-flexible tongues capable of being sprung towards and away from the axis of the piston to decrease or increase the diameter thereof in the region of said tongues for the purposes: previously mentioned.

The slot -;in eachhalf section of the skirt resembles substantially the shape of the let-- view, my invention consists in theioovel feater M-and'it extendsj-with relation to the half section .of'the 'skirtiin which it is cut as follows: Assuming the piston to be in updicated at 20, to a point adjacent to the otherbo'ss 18. It then is extended downwardly, or, in other "words, towards the open .end of the piston a suitable distance, either parallel or substantially parallel to the longitudinal axis of the piston, as indicated at '22. It then is extended .in the direction of the boss 18 first mentioned diagonally downward or at an incline towards the open end of the piston as indicated at 24,- this portion '24 underlying the portion 20, or, in other packing rings and provided at diametrical- .ly' opposite points internally, intermediate its ends, with bosses-18 bored for the reception of a wrist pin. Preferably I form my iston from gray iron, although it may be ormed from aluminum or any other suitable material, and I construct its walls relatively thin to secure not only'the greatest I flexibility in the skirt portion thereof, but 50 also to reduce-the weight of the piston to a minimum consistent with strength, vso as to secure so-far as possible the advantages of lightness in consideration of the problemsof inertia and kinetics presented by .a device of this kind.

For convenience in further-describing my words, being formed within the samecircumferential limits of the piston as said portion 20. Next, it again is extended downwar-(11y or towards the open end of the piston a short distance, either parallel or sub stantially parallel to the longitudinal axis of the pistonas indicated at 26. Next, it again is extended in the direction of the second mentioned zboss 18 diagonally downward or at an incline towards the open end of the piston as indlcated at 28, said portion 28 underlyingv or being disposed within the same circumferential limits of the piston as portions 20, 24. Next, it again is extended downwardly or' towards the 0' en end of the piston, parallel or substantia 1y parallel to the longitudinal axis of the piston as indicated at 30 and finally is extended, as at 32, near the lower or open end of the piston, parallel or, substantially parallel to the portion in underlying relation to or within the same circumferential piston limits as portions 20, 24 and 28. The result is that direction and the intermediate tongue 36 having its free endfacing. in an opposite direction. It will here be noted that the slots do not open through the lower or open end of the piston, but are disposed entirely between theends of the piston, the lower end portion-thereof being continuous and uninterrupted so as to provide a piston having maximum strength at this point despite the flexible-nature of the tongues 34, 36 and 38 which form the major portion of its skirt.

Formed integrally with each tongue 34, 36 and 38 on the inner face thereof at its base, that is, at the juncture of each tongue with the skirt portion proper of the piston, is a rib 40, split as at 42, so that one portion 40 thereof may be said'to be on the tongue and the other'portion 40 "thereof on the Y skirt portion proper. A bolt 44 having a tapered head 46 is passed through a suitable enlargement of'the split 42 with the tapered head thereof enga ing adjacent edges of the 4 portions 40, 40 0 the rib at one side thereof, and a tapered nut 48 is threaded on said bolt with its tapered portion engaging adjacent edges'of said portions 40, 40 at the opposite'side of the rib. As a result of this arrangement it is obvious that by rotatably adjusting the bolt 44 in one direction, the tapered head and nut may be drawn towards one another thereby to spread the rib portions 40, 40 and thus expand or force the tongue outwardly thereby to increase the eflective diameter of: the piston, while on the other hand, by rotatably adjusting the bolt in an opposite direction the spreading force of the tapered head and nut may be removed, so that the tongue may contract or be moved inwardly to lessen the effective diameter of the piston. Although not absolutely necessary, a lock nut 50 may be threaded on the bolt to secure the tapered nut 48 thereon and to guard against accidental loss of the bolt from the rib.

From the foregoing description considered ings it is apparent that I have provided a piston including a, skirt portion composed of tongues which may yield inwardly to per-' mit the piston to move freely within a piston under conditions which might otherwise cause the same to fit too closely withinthe cylinder with consequent binding action and scoring of either the cylinder or piston or both; that I have provided a simple yet eifective means for expanding or forcing the tongues outwardl to increase the eflective diameter of the piston, so that same may be adjusted to compensate for wear; that the lower or open end portion of the skirt is continuous whereby its strength is substantially unaffected by slotting the intermediate portions of the skirt; that the piston may be formed relatively light in weight and that,

above all, it is simple and cheap to produce, strong, durable and thoroughly reliable and eflicient in use.

Various modifications and desirable additions maybe made in and to the particular structural arrangement disclosed herein within the spirit and scope of my invention as defined in the appended claims.

I claim: a

1. A piston including a skirt slotted to produce a flexible tongue, a split rib formed on theinner face of said skirt partly on said rib and partly on the body portion proper of the skirt, and screw means between adjacent edges of said rib formed by said split operable to spread the two portions of said rib with respect to one another thereby to adjust said tongue outwardly with respect to the axis of the skirt.

2. A piston including a skirt slotted to produce a flexible tongue, a split rib formed on the inner face of said skirt partly on said rib and partly on the body portion proper of the skirt, a screw member extending through said rib at the split thereof, and.

a tapered nut threaded on said screw member with the tapered portion thereof entering the split in said rib.

3. A piston including a skirt slotted to produce a flexible tongue in the side thereof, asplit rib-formedon the inner face of said skirt partly on said rib and partly on the body portion proper of the skirt, and means constantly associated with said rib for spreading the portion thereof ,on the rib with respect to the portion thereof on the sln'rt proper, thereby to adjust said tongue outwardly with respect to the axis of the In testimony whereof I hereunto afiix m signature.

' GEORGE E. BRENT. 

